Herbicide failures cost Australian farmers millions of dollars each year — and the majority are preventable. Here are the most common mistakes and how to avoid them.
1. Wrong Water Volume
Most herbicide labels specify a water volume range. Too little water and you get poor coverage and increased drift risk. Too much and you dilute the product below effective concentration. Always check the label and calibrate your sprayer before each season. Browse our sprayer range including boom sprays and knapsacks.
2. Spraying at the Wrong Growth Stage
Most herbicides have a target growth stage window. Spraying too early or too late dramatically reduces efficacy. Buffalo grass and paspalum are notoriously hard to kill when drought-stressed. Spray when actively growing.
3. Not Using an Adjuvant
Many herbicides require a surfactant or wetting agent to penetrate waxy or hairy leaf surfaces. Glyphosate on established weeds, triclopyr on woody weeds, and most grass selectives work significantly better with a quality adjuvant. Browse our Adjuvants & Wetting Agents — BS1000, Agral, and Hasten are the most widely used in Queensland.
4. Mixing Incompatible Products
Not all herbicides are compatible in the tank. Always perform a jar test before mixing new product combinations. Add products in the correct order: water first, then WP/WG products, then liquids, then adjuvants. Never mix concentrated products together before adding water.
5. Spraying in Unsuitable Conditions
Wind above 15 km/h causes drift. Temperature inversions at dawn and dusk trap droplets near the ground and increase off-target movement. Spray between 10am and 4pm in calm, stable conditions.
6. Ignoring Withholding Periods
All registered herbicides have withholding periods for grazing and re-cropping. Always read the current registered label before use and record every application. See our guide to understanding withholding periods.
Shop Herbicides and Adjuvants at TGRM
TGRM stocks a full range of herbicides, adjuvants, and calibration equipment. Our team can help you choose the right product and application method. Gympie QLD — 07 5482 1692.
Related reading: Serrated Tussock Control | Lantana & Woody Weed Control